unit (7) organic compounds

Practice 7-5Give the IUPAC name for each of the following:CH 2 - CH 3a) CH 2 = CH -CH 2 - CH 3 b) CH 3 - CH 2 -CH 2 - C = CH 2CHCH 3 CH 33c) d) CH 3 - C C - CH - CH - CH - CH 3AnswerCH 3a)1-buteneb) 2-ethyl-1-pentenec) 3-methylcyclohexene d) 4,5,6-trimethyl-2-heptyneCommon Names (non-IUPAC Names)A small number of organic compounds have common names (non-IUPAC) that are usedalmost exclusively to identify them. These compounds are usually the smallest membersof a particular class often containing only a few carbons. You need to be familiar to thesenames.CH 2 = CH 2 HC ≡ CHIUPAC name ethene ethyneCommon name ethylene acetylene7.9 Geometric IsomersUnlike alkanes, there is no free rotation around a carbon-carbon double bond in alkenes.If both carbons of the double bond have two different groups attached, cis and transisomers exist.Cis isomer: two substituted groups are on the same side of double bond.Trans isomer: two substituted groups are on opposite sides of double bond.7-14